1. Field of the Invention
The present invention relates to an improved aggregate building material employing recycled plastic waste.
2. Description of the Prior Art
Presently, plastics which are recycled are separated into constituent types of plastics which are then individually melted down before they can be reused. This requires vast amounts of man hours and processing time. Accordingly, only a small fraction of plastics used are recycled, the rest going into landfills, incinerators, and dumps. There is clearly a long-felt need for a way to reuse plastics without requiring such extensive effort and processing. The incorporation of plastics into building materials has been described in the prior art. For example, the improvement of an asphalt composition by inclusion therein of a prepared organic or plastic material is shown in U.S. Pat. Nos. 3,418,402, issued on Dec. 24, 1968 to Robert R. Grissom et al., and 3,778,397, issued on Dec. 11, 1973 to Charles R. Gannon et al. As taught in '397, plastic material may take the form of feedstock polymer or crumb rubber.
Incorporation of recycled solid wastes into a building material is taught in U.S. Pat. No. 3,801,358, issued to Meyer Steinberg et al. on Apr. 2, 1974, and Japanese Pat. Document 52-29704, issued to the Kajima Corp., and dated Nov. 10, 1972. In '358, the waste is treated, as by drying, heating, irradiating, and compacting, and is incorporated into a concrete mix. The aggregate is allowed to cure prior to treatment with a polymer. In the Japanese reference, granulated waste is mixed with mineral particles and combined with an asphalt binder.
Recycled plastic scrap is utilized in fabricating concrete blocks of predetermined shape and size, as seen in U.S. Pat. No. 4,427,818, issued to Richard C. Prusinski on Jan. 24, 1984. The process disclosed therein requires an intermediate step of heating the plastic.
Recycling waste, although in the form of incinerator ash, and not plastic scrap, is seen in the article taken from the Christian Science Monitor, as reported in Washington Home, issue of Oct. 3, 1991, and in U.S. Pat. No. 3,907,582, issued to C. Edward Walter on Sep. 23, 1975. The use of ground rubber tires and scrap plastic for application as aggregates in highway pavement is discussed in '582.
U.S. Pat. No. 3,941,607, issued to Albert Schuhbauer et al. on Mar. 2, 1976, discloses another example of using plastics as stiffening fillers to an aggregate building material.
Recycling plastics by fabricating articles therefrom is seen in U.S. Pat. Nos. 4,250,136, issued to Gary C. Rex on Feb. 10, 1981, and 5,073,416, issued to Roger W. Avakian et al. on Dec. 17, 1991. '136 discloses a laminated composite having small plastic beads. '416 teaches fixing plastic particulates in a matrix of chopped fibers.
None of the above inventions and patents, taken either singly or in combination, is seen to describe the instant invention as claimed.